EP 0 583 534 A, WO 94/04651 A, WO 98/13458 A and WO 2007/145963 A describe enzyme stabilization in liquid detergent compositions comprising a reversible peptide aldehyde protease inhibitor. WO 95/25791 A describes methods for manufacturing protease enzymes using non-protein protease inhibitors.
α-MAPI, antipain, GE20372A and chymostatin A, B and C are described as peptide aldehydes with activity as protease inhibitors: R. J. Broadbridge et al., Chem. Commun. (1998), 1449. E. Sarubbi et al., FEBS Letters, 319 (3), 253-256 (1993). I. J. Galpin et al., Int. J. Peptide Protein Res., 23, 1984, 477-486.